| Oscillatory potentials (OPs) are important part of the electroretinogram(ERG). Generally, OPs are the summating potentials originated rfom retinal rodpathway. But there is different performance between rod-and cone-driven OPs inmany hereditary retinal diseases. And animal models have become a veryimportant tool in study these diseases. In early time our laboratory found twoanimal models, which are retinal cone dysfunction (RCD) rats and congenitalstationary night blindness (CSNB) rats. And ERG shows that RCD rats loss thecone function, while CSNB loss the rod function and damage the cone pathway.With the two kinds of rat models to separate the rod and cone pathway, thisresearch comparison the characteristics of the rod-and cone-driven OPs andexplore its mechanisms, providing the basic experiment basis for studying theorigin of OPs and clinical diagnosis of the inherited retinal diseases. Materials and methods1. Utilized the technique of visual electrophysiology to record flash ERGof wild-type SD, RCD, CSNB rats and analyzed the characteristics of each ERGwaveform.2. The scotopic and photopicOPs were extracted rfom ERG withMatlab7.0Butterworth filtering wavesand the rfequency spectrum of the OPswas analyzed by fast Fourier transform.Results1.ERG a wave and b wave were showed under the dark adaptationcondition in both SD and RCD rats, but b wave was absent in CSNB rat and onlyabnormal a wave was present. Under the light adaptation condition, b wave wasseen in both SD and CSNB rats, but a wave and b wave of RCD rat were absent.2.Two peaks were exhibited in both SD and RCD rats under thedark-adaptation condition and high intensity of stimulate light at the lowerrfequency (domain rfequency) of75-110Hz,90-120Hz and high rfequency(minor rfequency)90-120Hz,110-135Hz respectively. In various intensities ofstimulate light, CSNB rats appeared a peak at70-100Hz.3.In light-adaptation and various intensities of stimulate light, therfequency peaks were seen at75-95Hz and70-85Hz rfom both SD and CSNBrats respectively. However, under the light adaptation condition, only one peakwas seen in SD and CSNB rats at the75-95Hz and70-85Hz respectively.Conclusions1. Our study verified that retinal cone function of RCD rats entirely absentand rod function of CSNB rats completely missing along with destruction of cone function, and found the retinal optic rod-cone interaction in some stimulatelight.2. The experiment implied that rod-and cone-driven OPs have differentspectral characteristics. Rod-driven OPs have two rfequency peaks and give morecontribution than cone-driven OPs. |
